food and nutrition evaluation...
TRANSCRIPT
Nutrition and Food Evaluation
PROTEIN
By. Jaya Mahar Maligan
Laboratorium Nutrisi Pangan dan Hasil Pertanian
Program Studi Ilmu dan Teknologi Pangan
Jurusan Teknologi Hasil Pertanian
FTP - UB
2013
• Complex Nutrition compound that contains of Nitrogen molecule, composed from amino acids with peptide bond.
• Protein has amina group (NH2) -> distinguished from Carbohydrate and Lipid
• Synthesize in plant and animal tissue
Protein
Protein
Protein
1. Essential for growth and tissue care
2. Essential compound precursor (enzyme, hormone, hemoglobin, neurotransmitter
3. Control body liquid balance (intracellular liquid, extracellular liquid and intravascular liquid)
Protein Function
4. Maintain accumulation of acid/base
5. Stimulate antibody production
6. Nutrient transporter (carrier protein)
7. Energy source (4kkal/gr)
Protein Function
Source :
1. Endogen protein : body tissue
2. Eksogen protein : diet
Synthesize :
1. Essential protein
2. Non essential protein
Protein Classification
• Essential :
Leu, Ile, Val, Trp, Phe, Thr, Lis, His, Met
• Conditional Essential :
Pro, Ser, Arg, Cys, Gly, Tyr
• Non Essential :
Ala, Gln, Glu, Asp, Asn
Protein Classification
Amino Acid Precursor
• Met, Ser : Cys
• Phe : Tyr
• Glu, Gln, Asp : Arg
• Glu : Pro
• Ser : Gly
Protein Classification
Amino Acid Function :
• Incomplete protein
ex. Zein (jagung)
• Complete protein
ex. Glisin (soy), glutenin (wheat), animal prot
• Partially complete protein
ex. Gliadin (wheat), legumin (beans)
Protein Classification
Protein Form:• Fibrous : higher mechanical stress, low
solubilityex. Collagen, elastin, keratin, miosin
• Globular : more soluble, easy denaturedex. Albumin, globulin, histon, protamin
• Conjugated protein (bounded to prosthetic groups)ex. Lipoprotein, phosphoprotein, nucleoprotein
Protein Classification
Protein Structure
Denaturation• is a process in which proteins lose the tertiary
structure and secondary structure then present in their native state,
• by application of some external stress or compound such as a strong acid or base, a concentrated inorganic salt, an organic solvent (e.g., alcohol or chloroform), or heat
• Increase the protein digestibility
Protein Denaturation
Gastric digestion
• Parietal cell -> HCl : protein denaturation
• Chief cell -> proenzym of Protease gastric : pepsinogen(activated by HCl) -> pepsin
• Cleavage the peptide bond -> polipeptide, proteose, pepton
Protein Digestion
Small Intestine (Duodenum)
• Proenzym of pancreatic protease (trypsinogen, chemotrypsinogen, proelastase, procarboxypeptidase)
• Activated by enterokinaseenzym of mucosa cell and tripsin
• Digestion : 30% amino acid, 70 % (dipeptide, tripeptide and more)
Protein Digestion
Small Intestine (Jejunum)
• Protease (carboxypeptidaseand aminopeptidase : di and tripeptidase)
• Digestion : dipeptide
Protein Digestion
Small Intestine (Ileum)
• Protease (carboxypeptidase, aminopeptidase and dipeptidase)
• Digestion : amino acid
• Absorption
Protein Digestion
• Amino acid absorp by the villyof ileum mucosa -> diffusion and active transport
• Distribute to amino acid pool (blood and intracellular tissue)
• Transport through blood to the liver and circulate to the cells all over the body
Protein Absorption & Transport
Protein Metabolism
Liver
• Amino acid Oxidation
• Synthesize plasma protein
• Protein deamination -> urea from urine
Cell
• Synthesize new protein
• High protein content will recirculate to liver
• Deaminated amino acid will go to energy metabolism (ketogenic acid)
Protein Metabolism
Protein Metabolism
Protein Metabolism
AA Pool
NE-AA Synthesize
Endogen Source : Tissue, enzyme, hormone, etc
synthesize and degradation
Another tissue material (NE prot) : purin, pirimidin, kolin, bile acid, melanin, etc
conversion
Energy Metabolism
Exogen Source : Food
Digestion and absorption
Excreta
Excretion : kidney, skin, urine
Based on :
• Essential amino acid
• Amino acid balance
• Fitness to purpose
• Digestibility
Nutrition Value of Protein
Influenced by :
• Processing technique
• Anti-nutrition compound
• Reaction between protein and another compound
Protein Digestibility
Nilai Gizi Protein
1. Amino acid
• Essential Amino Acid
• Amino acid balance
• Limiting Amino Acid
Nuts : metionin, Cerealia : lisin
Evaluasi Nilai GiziProtein
1. Teoritisnilai biologis suatu protein dibatasi oleh proporsirelative asam amino esensial yang terkandung didalamnya
• Skor Asam Aminomembandingkan kandungan AA antara bahan ujidengan protein patokan (AA yg paling defisien)
• PDCAAS (Protein Digestibility Corrected Amino Acid Score )Peringkat kualitas protein ditentukan dengan caramembandingkan profil asam amino protein darimakanan tertentu terhadap standar profil asam amino
• Skor Asam Amino= mg AA per gram protein uji x 100
mg AA yang sama per gram protein patokan
•PDCAAS = Skor AAE terendah x DC prot sejati
Protein PER Digestibility AAS PDCAAS
Egg 3.8 98 121 118
Cow’s milk 3.1 95 127 121
Beef 2.9 98 94 92
Soy 2.1 95 96 91
Wheat 1.5 91 47 42
Evaluasi Nilai GiziProtein
2. In VitroUji invitro : murah, singkat
• Penentuan aktivitas antitripsin dan antikimotripsin(Berdasarkan penurunan aktivitas hidrolisis tripsinpada suatu substrat)
• Penentuan aktivitas hemaglutinin(aktivitas hemaglutinin ekstrak kacang-kacangandidasarkan pada kemampuannya untuk mengaglutinasisel darah merah)
• Penentuan daya cerna protein(pepsin-tripsin, pepsin-pankreatin dan teknikmultienzim : tripsin, kimotripsin dan peptidase)
Evaluasi Nilai GiziProtein
3. In VivoUji invivo : hewan coba & manusia(biologis)
• Protein Efficiency Ration (PER)• Net Protein Ratio (NPR)• Biological Value (BV)• Net Protein Utilization (NPU)• Daya Cerna Sejati (DC Sejati) / True
digestibility
Evaluasi Nilai GiziProtein
PER
• Metode ini dikembangkan oleh Osborne, Mendel dan Ferry tahun 1919, merupakanevaluasi nilai gizi protein yang banyakdigunakan.
• Telah ditetapkan sebagai metode resmi FDA untuk penetapan mutu protein dalamnutrition labelling.
• PER dilakukan selama 28 hari pada hewancoba tikus, menggunakan jenis pakanstandart (AIN/ANRC).
Evaluasi Nilai GiziProtein
Evaluasi Nilai GiziProtein
PER• PER sampel = perub BB / jumlah protein konsumsi• PER kasein terkoreksi = 2.5 / PER kasein teranalisis• PER terkoreksi = PER sampel / PER kasein terkoreksi
Evaluasi Nilai GiziProtein
NPR
• NPR dikembangkan untuk memecahkan masalah teoritispada PER, dimana dalam penetapan PER semua protein yang dikonsumsi diasumsikan digunakan semua untukpertumbuhan, tidak mengantisipasi fungsi protein pemeliharaan.
• Pelaksanaan NPR sama dengan PER, hanya terdapatgrup tikus yang diberi ransum non protein dan lama waktu NPR hanya 10 hari
Evaluasi Nilai GiziProtein
BV, DC dan NPU
• Metode ini dikembangkan untukmengevaluasi protein secarabiologis dengan menggunakansubjek manusia, namun padaperkembangan selanjutnyametode BV ini diadopsi untukdilakukan pada hewan coba tikus
Evaluasi Nilai GiziProtein
Evaluasi Nilai GiziProtein
NPU perbandingan antara jumlah nitrogen yang diretensi dalam tubuh denganjumlah nitrogen yang dikonsumsi.
NPU = N konsumsi – (N feses - N metabolik)-(N urine – N endogen) x 100N yang dikonsumsi
Studi Kasus
1. Jelaskan bagaimana kecernaan protein untuk produkdendeng dan tauge !
2. Hitung nilai PER terkoreksi dari bahan XY jika diketahuiPER kasein teranalisis 2,35. Perubahan berat badantikus rata-rata dari 213 g menjadi 249 g selama masapemeliharaan 30 hari dengan asupan pakan XY. Reratajumlah konsumsi pakan 19.5 gr/hari dan kadar protein bahan XY adalah 76%.
3. Jelaskan arti nilai PER dari soal no 2 tersebut!
4. Tentukan nilai NPR soal no. 2 jika diketahui padakelompok kontrol terjadi penurunan BB tikus sebanyak5 gr selama masa pemeliharaan!